Cell biologists recently mapped the signaling pathways (small GTPases to WASP/Scar proteins to Arp2/3 complex) that control the assembly of actin filaments that drives forward the leading edge of motile cells. Independently, neurobiologists have identified key plasma membrane receptors for soluble and matrix molecules that guide the motility of neuronal growth cones to their targets during the hard wiring of the nervous system, a process that produces approximately one million miles of neuronal process in the human brain! Throughout life, synaptic connections are remodeled in response to activity by processes that also appear to depend on actin assembly. Although cell biologists working on mechanisms of cellular motility and neuroscientists working on brain development and plasticity are investigating on the same process, communications have been minimal. One neurobiologist commented that "these groups have rarely if ever been seen in the same room." The time is now opportune for a symposium that will bring together scientists working on both actin-based motility and development of nervous systems. We are confident that mutually beneficial insights will emerge from learning about each others work.